Value of trees
In a study conducted by the U.S. Department of Agriculture Forest Service, experts determined the value of trees to a homeowner or community. The "Midwest Community Tree Guide" determined the annual benefits and costs over a 40-year planning horizon for newly planted trees in three residential yard locations (east, south and west of the residence) and a public street side or park location. Prices were assigned to each cost (e.g., planting, pruning, removal, irrigation, infrastructure repair, liability) and benefit (e.g., heating/cooling energy savings, air-pollutant mitigation, storm water-runoff reduction) through direct estimation and implied valuation of benefits as environmental externalities. This approach made it possible to estimate the net benefits of plantings in "typical" locations and with "typical" tree species.
The average annual net benefits (benefits minus costs) per tree increased with mature tree size:
The findings suggest that average annual net benefits from large trees, like the red oak and hackberry, can be substantially greater than those from small trees like crabapple. Average annual net benefits for the small, medium and large public trees were $4, $16 and $58, respectively. The largest average annual net benefits, however, stemmed from yard trees opposite the west-facing wall of a house: $15, $34 and $76 for small, medium and large trees, respectively.
The large residential tree opposite a west house wall produced a net annual benefit of $123 at year 40. In the same location, 40 years after planting, the red oak and crabapple produced annual net benefits of $58 and $45.
Net benefits for the yard tree opposite a west house wall increased with size when summed over the entire 40-year period:
Twenty years after planting, annual net benefits for a yard tree located west of a home were $87 for a large tree, $45 for a medium tree and $20 for a small tree. For a large hackberry 20 years after planting, the total value of environmental benefits alone ($77) was five times greater than the annual costs ($15). Similarly, environmental benefits totaled $46 and $24 for the red oak and crabapple, while tree-care costs were substantially less, $13 and $8, respectively.
Reach Sara Busse at sara.bu...@wvgazette.com or 304-348-1249.